![]() ![]() ; ; Streb, Christoph Klaus ![]() Scientific Conference (2005) Detailed reference viewed: 29 (0 UL)![]() ![]() ; ; et al Scientific Conference (2005) Detailed reference viewed: 33 (0 UL)![]() ![]() ; ; et al Scientific Conference (2005) Detailed reference viewed: 42 (0 UL)![]() ![]() ; ; Streb, Christoph Klaus ![]() Scientific Conference (2005) Detailed reference viewed: 53 (0 UL)![]() ![]() ; ; Streb, Christoph Klaus ![]() in Journal of Change Management (2005), 5(1), 57-69 Detailed reference viewed: 116 (0 UL)![]() ![]() Danoy, Grégoire ![]() ![]() in 9th International Conference on Knowledge-Based Intelligent Information and Engineering Systems (KES 2005) (2005) Detailed reference viewed: 172 (7 UL)![]() ![]() Haan, Serge ![]() ![]() in Cellular Signalling (2005), 17(12), 1542-50 IL-6-type cytokines play an important role during inflammation and the immune response. In addition, they are involved in haematopoiesis, liver and neuronal regeneration, embryonic development and ... [more ▼] IL-6-type cytokines play an important role during inflammation and the immune response. In addition, they are involved in haematopoiesis, liver and neuronal regeneration, embryonic development and fertility. We found that IL-6-type cytokine stimulation of cell lines and primary human macrophages results in a different distribution of the DNA-binding competent STAT dimer species in the cytosol and nucleus as demonstrated by electrophoretic mobility shift assays. In the absence of detergent, STAT3/STAT3, STAT1/STAT3 were the predominant species in the cytoplasm while STAT3/STAT3 was predominant in the nucleus. However, in detergent containing total cellular lysates and nuclear fractions prepared with detergent containing buffers, the STAT1/STAT1 homodimer was as prominent or even more prominent than STAT3/STAT3 and STAT1/STAT3. We were interested in the cause of this discrepancy since STAT1-regulated genes have not been described to be expressed upon IL-6-type cytokine stimulation. In addition to the more transient STAT1 activation, IL-6-type cytokines such as IL-6 and OSM lead to a much less efficient STAT1 activation compared to the potent STAT1 activators IFNgamma and IFNalpha. Studies with STAT1-deficient cells revealed that STAT1 activation does not seem to be an important competitive process to STAT3 activation arguing again for a very inefficient STAT1 activation upon IL-6-type cytokine stimulation. We also describe that pY-STAT3 is much more efficiently shuttled into the nucleus than pY-STAT1. [less ▲] Detailed reference viewed: 132 (2 UL)![]() ![]() ; ; et al in Journal of Biological Chemistry (2005), 280(36), 31478-88 The suppressors of cytokine signaling (SOCS) are negative feedback inhibitors of cytokine signal transduction. SOCS3 is a key negative regulator of interleuking-6 (IL-6) signal transduction. Furthermore ... [more ▼] The suppressors of cytokine signaling (SOCS) are negative feedback inhibitors of cytokine signal transduction. SOCS3 is a key negative regulator of interleuking-6 (IL-6) signal transduction. Furthermore, SOCS3 was shown to be phosphorylated upon treatment of cells with IL-2, and this has been reported to regulate its function and half-life. We set out to investigate whether SOCS3 phosphorylation may play a role in IL-6 signaling. Tyrosine-phosphorylated SOCS3 was detected upon treatment of mouse embryonic fibroblasts with IL-6. Interestingly, the observed SOCS3 phosphorylation does not require SOCS3 recruitment to phosphotyrosine (Tyr(P)) 759 of gp130, and the kinetics of SOCS3 phosphorylation do not match the activation kinetics of the Janus kinases. This suggests that other kinases may be involved in SOCS3 phosphorylation. Using Src and Janus kinase inhibitors as well as Src kinase-deficient mouse embryonic fibroblasts, we provide evidence that Src kinases, which we found to be constitutively active in these cells, are involved in the phosphorylation of IL-6-induced SOCS3. In addition, we found that receptor-tyrosine kinases such as platelet-derived growth factor receptor or epidermal growth factor receptor can very potently phosphorylate IL-6-induced SOCS3. Taken together, these results suggest that SOCS3 phosphorylation is not a JAK-mediated phenomenon but is dependent on the activity of other kinases such as Src kinases or receptor-tyrosine kinases, which can either be constitutively active or activated by an additional stimulus. [less ▲] Detailed reference viewed: 64 (0 UL)![]() ; Kohns, Oliver ![]() in Wirkendes Wort (2005), 55(3), 389-403 Detailed reference viewed: 102 (4 UL)![]() Kohns, Oliver ![]() in Karschnia, Alexander; Kohns, Oliver; Kreuzer, Stefanie (Eds.) et al Zum Zeitvertreib : Politik – Institutionen – Lektüren – Bilder (2005) Detailed reference viewed: 417 (3 UL)![]() ![]() ; ; et al in Journal of Biological Chemistry (2005), 280(23), 21700-5 Transcription factors of the STAT (signal transducer and activator of transcription) family are important in signal transduction of cytokines. They are subject to post-translational modification by ... [more ▼] Transcription factors of the STAT (signal transducer and activator of transcription) family are important in signal transduction of cytokines. They are subject to post-translational modification by phosphorylation on tyrosine and serine residues. Recent evidence suggested that STATs are methylated on a conserved arginine residue within the N-terminal region. STAT arginine methylation has been described to be important for STAT function and loss of arginine methylation was discussed to be involved in interferon resistance of cancer cells. Here we provide several independent lines of evidence indicating that the issue of arginine methylation of STATs has to be reassessed. First, we show that treatment of melanoma and fibrosarcoma cells with inhibitors used to suppress methylation (N-methyl-2-deoxyadenosine, adenosine, dl-homocysteine) had profound and rapid effects on phosphorylation of STAT1 and STAT3 but also on p38 and Erk signaling cascades which are known to cross-talk with the Jak/STAT pathway. Second, we show that anti-methylarginine antibodies did not precipitate specifically STAT1 or STAT3. Third, we show that mutation of Arg(31) to Lys led to destabilization of STAT1 and STAT3, implicating an important structural role of Arg(31). Finally, purified catalytically active protein arginine methyltransferases (PRMT1, -2, -3, -4, and -6) did not methylate STAT proteins, and cotransfection with PRMT1 did not affect STAT1-controlled reporter gene activity. Taken together, our data suggest the absence of arginine methylation of STAT1 and STAT3. [less ▲] Detailed reference viewed: 136 (2 UL)![]() ![]() ; Haan, Serge ![]() in Journal of Biological Chemistry (2005), 280(27), 25760-8 The presence of a Src homology 2 (SH2) domain sequence similarity in the sequence of Janus kinases (Jaks) has been discussed since the first descriptions of these enzymes. We performed an in depth study ... [more ▼] The presence of a Src homology 2 (SH2) domain sequence similarity in the sequence of Janus kinases (Jaks) has been discussed since the first descriptions of these enzymes. We performed an in depth study to determine the function of the Jak1 SH2 domain. We investigated the functionality of the Jak1 SH2 domain by stably reconstituting Jak1-defective human fibrosarcoma cells U4C with endogenous amounts of Jak1 in which the crucial arginine residue Arg466 within the SH2 domain has been replaced by lysine. This mutant still binds to the receptor subunits gp130 and OSMR. Moreover, the SH2 R466K mutation does not affect the subcellular distribution of Jak1 as assessed by cell fractionation and confocal microscopy of cells expressing endogenous levels of non-tagged or a yellow fluorescent protein (YFP)-tagged Jak1-R466K, respectively. Likewise, the signaling capacity of Jak1 was not affected by this point mutation. However, we found that the SH2 domain is structurally important for cytokine receptor binding and surface expression of the OSMR. [less ▲] Detailed reference viewed: 132 (2 UL)![]() ![]() ; ; et al in Zeitschrift für Orthopadie und Ihre Grenzgebiete (2005), 143 Detailed reference viewed: 142 (0 UL)![]() Klump, Rainer ![]() Book published by IFA, Institut für Asienkunde (2005) Detailed reference viewed: 98 (0 UL)![]() ![]() Klump, Rainer ![]() in Klump, Rainer; Mutz, Gerhard (Eds.) Modernization and social transformation in Vietnam (2005) Detailed reference viewed: 78 (0 UL)![]() ![]() Klump, Rainer ![]() in Klump, Rainer; Mutz, Gerhard (Eds.) Modernization and social transformation in Vietnam (2005) Detailed reference viewed: 28 (0 UL)![]() ![]() Klump, Rainer ![]() in Goldschmidt, Nils (Ed.) Wirtschaft, Politik und Freiheit. Freiburger Wirtschaftswissenschaftler und der Widerstand (2005) Detailed reference viewed: 39 (0 UL)![]() ![]() Runte, Maren ![]() in Human Genetics (2005), 116(3), 228-230 Detailed reference viewed: 105 (0 UL)![]() Majerus, Benoît ![]() in Cahiers d'Histoire du Temps Présent = Bijdragen tot de Eigentijdse Geschiedenis (2005), (15), 65--81 Detailed reference viewed: 142 (5 UL)![]() ![]() Tkatchenko, Alexandre ![]() in JOURNAL OF PHYSICAL CHEMISTRY B (2005), 109(46), 21710-21715 A simple unequal-sphere packing (USP) model, based on pure geometrical principles, was applied to study the centered-rectangular iodine c(p x root 3)R30 degrees adlayer on the Au(111) surface, well-known ... [more ▼] A simple unequal-sphere packing (USP) model, based on pure geometrical principles, was applied to study the centered-rectangular iodine c(p x root 3)R30 degrees adlayer on the Au(111) surface, well-known from surface X-ray structure (SXS), low energy electron diffraction (LEED) and scanning tunneling microscopy (STM) experiments. To reproduce the exact patterns observed in experiments, two selective conditions-minimum average adsorbate height and minimum adlayer roughness-were imposed. As a result, a series of adlayer patterns with c(p x root 3)R30 degrees symmetry (2.3 < p < 3), with precise structural details, including atomic registry and identification of the p-bisector as the most likely trajectory for the iodine adatom movement during the so-called uniaxial compression phenomenon, were identified. In addition, using the same model, the difference between the iodine adlayer arranged in hexagonal and centered-rectangular c(p x root 3)R30 degrees patterns, as in the case of Pt(111) and Au(111) surfaces, was investigated. Qualitative and quantitative comparison shows that iodine adatoms in these two arrangements differ significantly in atomic registry, distance from the substrate, and the adlayer corrugation. Our findings could be of special interest in the study of the nature of the iodine adatom bonding to different substrates (i.e., Au vs Pt). [less ▲] Detailed reference viewed: 156 (1 UL) |
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